1. Field of the Invention
The present invention relates to a reset circuit and a reset method. Especially, the present invention relates to a reset circuit and a reset method for a communication device installed in an inaccessible place such as a remote place or a dangerous place like a high-altitude place.
2. Description of the Prior Art
Generally, for example, a reset circuit is applied to a communication processing circuit. FIG. 1 is a diagram showing a conventional reset circuit. Referring to FIG. 1, a communication processing circuit 13 is reset by a reset circuit 12. For resetting, software reset by a switch, software reset by software, power reset by a switch and the like are employed. The communication processing circuit 13 is reset by a system reset pulse 4 and a power reset pulse 6 output from the reset circuit 12.
The prior art described above is disclosed in the Japanese Patent application laid open No. 2000-276260 and in the Japanese Patent application laid open No. 10-11324.
The conventional reset circuit and the reset method have problems as below.
The first problem is that, in a communication device installed in an inaccessible place such as a remote place or a dangerous place like a high-altitude place where it is difficult to visit, it is difficult to operate the power switch of the main body of the device.
The second problem is that, in a communication device remotely installed, resetting by pressing a switch or resetting by software is impossible when there are problems with firmware or software.
Generally, for resetting a communication device, a switch or a multiplexed control signal has been used for resetting a power source or a system. Especially, in a communication device remotely installed, a power switch cannot be easily operated and the control signal cannot be used for resetting when there are problems with firmware or software of a communication device.